Valve actuator

ABSTRACT

Apparatus for operating a valve mounted in a flow line including a motor driving a threaded shaft having a traveling nut mounted thereon, support means supporting the motor so as to be substantially supported by the flow line such that the shaft is substantially free of extraneous forces; and, an actuating arm connecting the traveling nut to the valve whereby movement of the traveling nut opens and closes the valve.

United States Patent 1191 Thompson NOV. 27, 1973 VALVE ACTUATOR [76] 'Inventor: J a r ne s B. Thompson, 5405 Longmont, Houston, Tex. 77027 22 Filed: Apr. 20, 1972 [21] Appl. No.: 245,989

[52] US. Cl. 74/89.]5, 74/424.8 VA [51] Int. Cl. Fl6h 29/20 [58] Field of Search 74/89.15, 424.8 VA; 251/58, 130, 133, 134, 138

[56] 7 References Cited UNITED STATES PATENTS 3,318,171 5/1967 Wilkinson et al 74/89.15' X 2,930,252 3/1960 Sears et al 74/424.8 VA X 3,011,359 12/1961 Morrell. 74/89.l5 X

Primary ExaminerCharles J. Myhrc Assistant ExaminerF. D. Shoemaker Att0rneyPravel, Wilson & Matthews [5 7] ABSTRACT Apparatus for operating a valve mounted in a flow line including a motor driving a threaded shaft having a traveling nut mounted thereon, support means sup porting the motor so as to be substantially supported by the flow line such that the shaft is substantially free of extraneous forces; and, an actuating arm connecting the traveling nut to the valve whereby movement of the traveling nut opens and closes the valve.

10 Claims, 5 Drawing Figures VALVE AGTUATORJ'? BACKGROUND OF THE INVENTION The field of this invention is new and @improved svalve:

actuators.

Various types of I valve actuators havebeen=devised1 for applying substantial torque to rotatablevahkeele maintenance problems.

SUMMARY OF THE INVENTION The present invention relates to a new and improvedapparatus for providingsubstantial'torque forces-for opening and closing a valve mountedin'aflow line" wherein a motor means and threaded shaft are: driv ingly connected to move atraveling nut along :the shaft: An actuator arm is connected tothe valve and-is pivot-* whereby the actuator 'arm' is freed for manual move ment.

In one aspect of this invention, a support bracketis mounted onto the flow line to support the motor means directly above the flow line to substantially reduceex traneous forces acting to bend or bind the threade'd shaft connected to the motor-means. The threaded shaft is supported at both ends "bybearings to enhance free rotation.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top view-of the valve actuator of .the preferred embodiment of thisinvention illustrating. the

valve vin the open position;

FIG. 2 is a top viewof the valve actuator illustrating:

the valve in the closed position;

FIG. 3 is a side viewtaken along line- 33 of FIG. 2;

FIG. 4 is a sectional view of the'motor support means of this invention; and

FIG. 5 is an assembly view-of the releasable connection between the-valve actuator arm and the traveling nut.

DESCRIPTION OF THE PREFERRED" EMBODIMENT Referring to the drawings, the letter A generally designates the valve actuator of the preferred embodiment of this invention for moving a valve V mounted in flow I line F between open and closed positions-Basically, the valve actuator A includes a motor means'designated v dsignated as which ismounted directly on theflow "moving circular plate 100 underneath the motor line F by a support means ll. The motor means-10 is a coupling 14;-and, atraveling nut lS isthreadedly mounted on the threaded shaft12 whereby rotation of the shaft 12 causes the nut 15 tomove alongxthe shaft An actuating arm 16 is pivotally connected to the nut 15' at:endl6'a and isattachedtowalve stem l7 of the' valve V such'that'niovement of 'the nut '15 causes pivot ing of: the actuating arm l6-and-rotation-of the valvestem 17 in order-to move a'valve element (not shown) 2 attached to the valve stem 17between open and closed positions within the valve V.

The support means 11*is provided for mountingthe motor means 10 for pivotal movement directly over'the flow lineF so thatthemotor means 10'is completely supported on the flowline'F thereby'preventing-any' bendingor-binding forces from acting on thethreaded shaft l2. Referring in particular to FIGS. 3'and 4the support means 11 includes an upper' semi-circular bracket or collar 1 la having an upwardly extending vertical shaft base 11b as an integral part thereof. A flat circular mountingtplate .110 is mounted over and secured =to the' shaft base 1 lb by weldingor other suitable means. The upper collar l 1a-is mounted overand secured tothe flow line F by a lower semi-circular -bracket or collar 1 1 f which is attached to the upper col lat by: nut '-and bolt combinations 1 12. The motor 10a.

of'the motor means 10 is mounted in a motor mounting bracket-10b by any. suitable means. A flat, circular plate is 'attachedflto the underside of the motor mounting bracket 10b through tubular memeberslfldg which are welded to the top side of plate 100 and bolted by-nut and bolt combinations 10c to the motor mount ing. bracket 10b;

The plate-10c has an opening 10f which'hasa diameter slightly greater than thediameterof "the-shaft base 11bso that'the motor 10a can be mounted overthe shaftbase 11b in sucha position that the stationary plate and plate 100 are mounted for rotating and slidable movement with respect to each other.

A capv logris secured to the shaft base 1 lb by bolt 10h to maintain the motor 10a and slidable plate 100 in position withrepsect to the stationary base plate 110. In this'manner, the plate 10c which supports the motor 10h, is mounted for rotating and slidable movement with respect to the stationary plate 11. The supporting of the'motor 10a onthe plates 11c and 100 serves to distribute the weight of the motor and balance 'it about the baseshaft 11b. The motor 10a is thus mounted for pivotal movement directly onto and above the flow line F so that the flow line F completely supports the weight of the motor 10a thereby preventing any undue stress or'-bendi'ng1on the threaded shaft 12. Although the motorl0a isshown to be mounted through plates 10c and lie directly above the flow line'F; it should'be appreciated that the motor may be mounted indirectly with: respect to the flow'line F as long as the flow'line F fully supports the motor'such that no undue stress or bending-forces are applied to the threaded shaft 12.

An elongated support bar 18 is mounted onto the mounting bracket l0bby any suitable meanssuch as welding. The support bar 18 mounts the threaded shaft" 12 for-rotation in the following manner. The coupling 14*which-drivingly connects driving shaft l0i of the mojor 10a to end 12a of the threaded shaft 12 is positioned between upwardly extending supports 21a and 21bof a U-shaped support 21, which is mounted by suitable means to an end portion 18b of support bar 18." .The coupling 14 includes bearing surfaces which en gage the upwardly extending supports 21a and 21b thus mounting and supportingth'e end 12a of "the threaded shaft12 and the drive shaft 101 for rotation; End 12b of the threaded shaft 12 is mounted for rotation by means of a bearing 22 which is mounted in an upwardly extending L-shaped support 23, which is attached to the bar 18 by welding or other suitable means. In this manner, the threaded shaft 12 is secured at both ends 12a and 12b for rotation such that the threaded shaft is effectively secured against stress.

The traveling nut 15 includes a conventional ball bearing nut portion 15a having ball bearings helically aligned disposed on the inside thereof in threaded engagement with the threaded shaft 12 in order to reduce friction between the rotating threaded shaft 12 and the nut 15 as the nut moves along the shaft. A clevis connector member 15b is welded or otherwise attached to the ball bearing nut 15a for movement therewith. Referring to FIG. 5, the connector member 15b has a slot 150 machined therein and lugs 15d having aligned holes 15a to provide a clevis type of connection. The end portion 16a of the actuator arm 16 has a hole 16c therein which may be aligned with holes 15e in the lugs 15d in order to receive a releasable connecting pin 24. The releasable connecting pin 24 includes a ring 24a thereby allowing the pin 24 to be easily pulled out of the holes 152 and 160 to release the actuator arm 16 from connection with connector member 15b of the nut 15. The easy disconnection of the actuator arm 16 from the nut 15 allows the valve V to be manually opened and closed whenever desired.

The actuator arm 16 is releasably connected to the valve stem 17 in the following manner. A hole 16d having the configuration of the valve stem 17, which is keyed, is machined in end 16b of the actuator arm and a slot 16a is machined therein in communication with the hole 16d. A bolt 16f is threadedly mounted through the actuator arm 16 at the slot l6e such that tightening of the bolt 16b causes the slot 16e to reduce in width thereby reducing the size of the hole 16d so that the end 16b of the actuator arm 16 is secured about the valve stem 17. Whenever it is desired to disconnect the actuator arm 16 from the valve stem 17, the bolt 16b is loosened thereby increasing the size of the hole 16d to allow the end 16d of the actuator arm to be lifted off of the valve stem 17.

Limit means generally designated as 30 are mounted onto support bar 18 and with traveling nut 15 in order to limit the movement of the nut 15 along the threaded shaft 12 thereby limiting the amount of rotation of the actuator arm 16 and valve stem 17.

A limit switch 31 is mounted by means of screws such as 31a onto end 18a of the support bar 18. The limit switch 31 is of conventional construction and is electrically connected with electrical controls lj for the motor 100. Limit switch 32 is mounted at end 18b of the support bar by means of screws such as 32a and is also in electrical connection with the electrical controls The limit switch 31 is activated by depressing switch arm 31b and the limit switch 32 is activated by depressing switch arm 32b. The activation of either limit switch 31 or 32 opens the electrical circuit for the electrical controls l0j thereby shutting off the power to the motor 10a.

A T-shaped switch actuator bracket 33 is bolted onto connector member b of the nut 15 and includes a horizontally extending bar portion 33a. Actuator plates 34a and 34b are mounted by means of screws or other suitable means substantially near the ends of the horizontal bar portion 33a of the actuator element 33. The

actuator plate 34 is positioned such that it will engage and depress the trigger arm 31b of the limit switch 31 as the traveling nut 15 approaches end 12b of the threaded shaft 12. Similarly, the actuator plate 34b will engage and depress trigger element 32b as the traveling nut approaches the end 12a of the threaded shaft.

In operation and use of the valve actuator A of the preferred embodiment of this invention, the valve V is moved from the open position of FIG. 1 to the closed position of FIG. 2 in the following manner. Motor is actuated through the controls l0j in the conventional manner to cause rotation of threaded shaft 12. The rotation of the threaded shaft causes the traveling nut to move along the threaded shaft from the position near end 12b of the threaded shaft to end 12a of the threaded shaft. Due to the length of the actuator arm 16, and further to the force exerted on end 16a of the actuator arm by the traveling nut 15, a very high torque can be exerted on valve stem 17 of the valve V. As the valve actuator A moves from the position of FIG. 1 to the position of FIG. 2, the motor 10a continually pivots clockwise as the actuator arm 16 is pivoted clockwise by the traveling nut 15 moving along threaded shaft 12. It is to be noted that the motor 10a is supported directly over the pipes such that the weight of the motor does not exert any extraneous forces on end of the threaded shaft 12. The coupling 14 is secured by bearing means against the U-shaped support 21 thereby supporting end 12a of the shaft as well as motor shaft end 10i such that no extraneous forces, such as the force of resistance exerted through arm 16, can effect the rotation thereof.

As the nut 15 approaches end 12a of the threaded shaft 12, the actuator plate 34b mounted on the T-bar actuator element 33 engages and depresses trigger arm 32b to cause the limit switch 32 to open the circuit providing power to the electric motor 10a thereby cutting off the motor. The limit switch 32 is positioned such that the actuator arm 16 is moved exactly through an arc of 90 (or other are if desired) so that the valve element (not shown) attached to the valve stem 17 is moved exactly and accurately to its closed position. Similarly, whenever the valve actuator A moves the valve V from the closed position of FIG. 2 to the open position of FIG. 1, the actuator plate 34a depresses trigger arm 31b of the limit switch 31 thereby shutting off power to the mojor 10a. The actuator plate 34a and limit switch 31 are positioned such that the actuator arm travels in an arc of exactly 90 from the position illustrated in FIG. 2 to the position illustrated in FIG. 1.

The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials as well as in the details of the illustrated construction may be made without departing from the spirit of the invention. For example, the valve V may be any type of valve wherein the valve is opened or closed through rotation. It should also be understood that the motor means 10 and the limit switches 31 and 32 may be either electrically or pneumatically actuated.

I claim:

1. Apparatus for operating a valve mounted in a flow line, comprising:

motor means;

a threaded shaft drivingly connected to said motor means;

support means separate from said valve and pivotally mounting said motor means on said flow line, said support means including bearing support means for mounting said threaded shaft for rotation whereby said threaded shaft is substantially free of extraneous forces;

a traveling nut threadedly mounted with said threaded shaftiand an actuator arm connected to said traveling nut and to said valve whereby rotation of said shaft by said motor means causes said traveling nut and actuator arm to cooperate to move said valve between open and closed positions.

2. The structure set forth in claim 1, wherein said support means includes:

bracket means mounted on said flow line for directly suporting said motor means on said flow line whereby the weight of said motor means is substantially supported on said flow line.

3. The structure set forth in claim 2, wherein:

said bracket means mounts said motor means directly above said flow line.

4. The structure set forth in claim 1, wherein:

said bearing support means supports said threaded shaft at substantially the ends thereof.

5. The structure set forth in claim 1, including:

pivotal connecting means for pivotally connecting said actuator arm to said traveling nut. 6. The structure set forth in claim 1, including: releasable connecting means for releasably connecting said actuator arm to said traveling nut. 7. The structure set forth in claim 6, wherein said releasable connecting means includes:

said traveling nut having a clevis connection;

a pin attaching said actuator arm with said clevis connection, said pin being removable whereby said actuator arm is free for manual operation.

8. The structure set forth in claim 1, including:

limit means mounted with said bearing support means and with said traveling nut for limiting movement of said traveling nut along said threaded shaft.

9. The structure set forth in claim 8, including:

said motor means being electrically powered;

said limit means including limit switches mounted with said bearing support means in proximity to the ends of said threaded shaft; said limit switches being electrically connected to said motor means; and

said limit means further including an activating element mounted with said traveling nut for activating said limit switches whereby the movement of said traveling nut along said threaded shaft is limited.

It). The structure set forth in claim 1, wherein said support means includes:

bracket means mounted on said flow line and including a base shaft having a stationary plate attached thereto;

a motor bracket attached to said motor means and having a rotatable plate mounted thereon whereby said rotatable plate is slidably mounted on said stationary plate for rotation about said base shaft. 

1. Apparatus for operating a valve mounted in a flow line, comprising: motor means; a threaded shaft drivingly connected to said motor means; support means separate from said valve and pivotally mounting said motor means on said flow line, said support means including bearing support means for mounting said threaded shaft for rotation whereby said threaded shaft is substantially free of extraneous forces; a traveling nut threadedly mounted with said threaded shaft; and an actuator arm connected to said traveling nut and to said valve whereby rotation of said shaft by said motor means causes said traveling nut and actuator arm to cooperate to move said valve between open and closed positions.
 2. The structure set forth in claim 1, wherein said support means includes: bracket means mounted on said flow line for directly suporting said motor means on said flow line whereby the weight of said motor means is substantially supported on said flow line.
 3. The structure set forth in claim 2, wherein: said bracket means mounts said motor means directly above said flow line.
 4. The structure set Forth in claim 1, wherein: said bearing support means supports said threaded shaft at substantially the ends thereof.
 5. The structure set forth in claim 1, including: pivotal connecting means for pivotally connecting said actuator arm to said traveling nut.
 6. The structure set forth in claim 1, including: releasable connecting means for releasably connecting said actuator arm to said traveling nut.
 7. The structure set forth in claim 6, wherein said releasable connecting means includes: said traveling nut having a clevis connection; a pin attaching said actuator arm with said clevis connection, said pin being removable whereby said actuator arm is free for manual operation.
 8. The structure set forth in claim 1, including: limit means mounted with said bearing support means and with said traveling nut for limiting movement of said traveling nut along said threaded shaft.
 9. The structure set forth in claim 8, including: said motor means being electrically powered; said limit means including limit switches mounted with said bearing support means in proximity to the ends of said threaded shaft; said limit switches being electrically connected to said motor means; and said limit means further including an activating element mounted with said traveling nut for activating said limit switches whereby the movement of said traveling nut along said threaded shaft is limited.
 10. The structure set forth in claim 1, wherein said support means includes: bracket means mounted on said flow line and including a base shaft having a stationary plate attached thereto; a motor bracket attached to said motor means and having a rotatable plate mounted thereon whereby said rotatable plate is slidably mounted on said stationary plate for rotation about said base shaft. 